However, I also believe that children, although they seem the perfect candidates for discipleship, I do not think they're ready to make full commitments to God. They wouldn't know what they were in for; they wouldn’t understand the sufferings, joys and rewards of discipleship.
This text if from, ‘theologia.com’. It shows a speech made Paul. It is about children being Christians.
“You shall teach them diligently to your sons and shall talk of them when you sit in your house and when you walk by the way and when you lie down and when you rise up. And you shall bind them as a sign on your hand and they shall be as frontals on your forehead. And you shall write them on the doorposts of your house and on your gates.”
This passage shows us that parents are to teach their children in God’s love and grace. They have the covenant promises of God to assure them and their children that God loves both them and their children. They must educate their children on how one should live as God’s possession.
Parents today sometimes resist this because they know that not all children of Christians grow up to continue in the faith in which they were raised. But text above, from Deuteronomy addresses that issue. God’s love can turn to jealousy if people grow up to reject it in unbelief.
The New Testament contains plenty of warnings against this as well. In John 15.1-11 Jesus both assures the disciples that they are, ‘fruit-bearing branches growing out of him’, and warns them that if they stop abiding in him that they will be cut out as fruitless branches. In Romans 11.17-22 Paul insists that believers are members of God’s covenant people but warns them of being cut off if they were to become unbelievers. ‘We should raise our children as Christians, encouraging both them and ourselves to run the race set before us’ (Hebrews 12.1).
The Bible tells us that children are a gift from God, specially created for His pleasure and divine purpose (Psalm 127:3-5, 139:13-16). God has entrusted us with our children for a very short time, during which parents have the responsibility of training, instructing, nurturing, and disciplining them. Ephesians 6:4 says, "Fathers, do not provoke your children to anger, but bring them up in the discipline and instruction of the Lord."
Not all types of baptism allow children to be baptised, for example, Believer’s Baptism. To take part in Believer’s Baptism you must believe in God, confess Jesus as Lord, be willing to be disciples of Jesus and be those who repent evil. A child would not be able to make this decision so Believer’s Baptism doesn’t allow children to be baptised. There are others, who believe that they are bringing the child up to be baptised and that they will then not need to be baptised again when they become believers.
Catholics believe that during baptism, the child’s sins are forgiven and the child can now enter the kingdom of God. As the children are to young, in the catholic baptism, the parents choose Godparents to support the child when they are baptised. Baptism brings discipleship
It is important that Christian parents teach their children the Word of God from a young age, showing them how to use it into their daily lives, trusting continually in God. Spiritual training is even more important than academic training, and it doesn't happen by accident; it must be purposeful and habitual.
I see why some people agree with that children cannot be Christians but I feel that this case is far weaker than why children can be Christians. Children might not know what they are fully committing to and are quite young to make a choice. It is important that we make the right choice for the child, and you might want a child to wait until they are older, so they can make the choice for themselves. I also feel that it is very important to ‘nudge’ the child into making the decision of God at an early age, for example, you can make the Sunday Church a daily routine in their lives. It shows them that there are options and the right one should be taken, by becoming a Christian.